Latch hooks, latch housings, and latch assemblies

ABSTRACT

Latch housing assemblies, latch hook assemblies, and latch assemblies are disclosed. Various disclosed latch housing assemblies include a latch pin coupled to an inner housing, and an outer housing having an inner surface coupled to an outer surface of the inner housing via at least one of a fuse pin and a spring. Various disclosed latch hook assemblies include a latch hook coupled to a latch housing, a weak point in the latch housing disposed between an inboard mount and an outboard mount, and a catch member mounted to the inboard mount and the outboard mount. Various disclosed latch assemblies include a latch housing, a bolt, and a deformable bushing at least partially surrounding the bolt, the deformable bushing configured to deform about a radius in response to a compressive load of about 1,000 lbf to about 3,000 lbf.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, and claims priority to, and thebenefit of U.S. Non-Provisional application Ser. No. 14/262,463,entitled “LATCH HOOKS, LATCH HOUSINGS, AND LATCH ASSEMBLIES,” filed onApr. 25, 2014, is hereby incorporated by reference in its entirety.

FIELD

The present disclosure relates to latch hooks, latch housings, and latchassemblies capable of being used in an aircraft.

BACKGROUND

Latch hooks, latch assemblies, and latch housings are commonly used inthe nacelle of an aircraft, for example, in fan cowls and the innerfixed structures of thrust reversers. Thrust reversers may typically bestructurally sized based on an overpressure event (e.g., a duct burstevent) to allow for release of the overpressure. Thus, some inner fixedstructures are sized to withstand the overpressure, increasing theweight of the fan cowls and thrust reversers, which may increase fuelcosts throughout the life of the aircraft.

SUMMARY

Latch housing assemblies are provided comprising a latch pin coupled toan inner housing and an outer housing having an inner surface coupled toan outer surface of the inner housing via at least one of a fuse pin anda spring.

A latch hook assemblies are provided comprising a latch hook coupled toa latch housing, a weak point in the latch housing disposed between aninboard mount and an outboard mount, and a catch member mounted to theinboard mount and the outboard mount.

A latch assembly comprising a latch housing, a bolt, and a deformablebushing at least partially surrounding the bolt, the deformable bushingconfigured to deform about a radius in response to a compressive load ofabout 1,000 lb_(f) to about 3,000 lb_(f).

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements.

FIG. 1 illustrates an inner fixed structure of a thrust reverser, inaccordance with various embodiments;

FIG. 2A illustrates a latch assembly, in accordance with variousembodiments;

FIG. 2B illustrates a latch housing and bushing, in accordance withvarious embodiments;

FIG. 2C illustrates a latch housing and bushing during an overpressureevent, according to various embodiments;

FIG. 3A illustrates a latch housing assembly, in accordance with variousembodiments;

FIG. 3B illustrates a latch housing assembly during an overpressureevent, in accordance with various embodiments;

FIG. 3C illustrates a latch housing assembly, in accordance with variousembodiments;

FIG. 4A illustrates a fuse pin, in accordance with various embodiments;

FIG. 4B illustrates a fuse pin during an overpressure event, inaccordance with various embodiments;

FIG. 5A, 5B, 5C, illustrate a latch hook assembly, in accordance withvarious embodiments;

FIG. 5D illustrates a latch hook assembly during an overpressure event,in accordance with various embodiments; and

FIG. 5E illustrates a latch hook assembly during an overpressure event,in accordance with various embodiments.

DETAILED DESCRIPTION

The detailed description of exemplary embodiments herein makes referenceto the accompanying drawings, which show exemplary embodiments by way ofillustration and their best mode. While these exemplary embodiments aredescribed in sufficient detail to enable those skilled in the art topractice the disclosure, it should be understood that other embodimentsmay be realized and that logical, material, and mechanical changes maybe made without departing from the spirit and scope of the disclosure.Thus, the detailed description herein is presented for purposes ofillustration only and not of limitation. For example, the steps recitedin any of the method or process descriptions may be executed in anyorder and are not necessarily limited to the order presented.Furthermore, any reference to singular includes plural embodiments, andany reference to more than one component or step may include a singularembodiment or step. Also, any reference to attached, fixed, connected orthe like may include permanent, removable, temporary, partial, fulland/or any other possible attachment option. Additionally, any referenceto “without contact” (or similar phrases) may also include reducedcontact or minimal contact.

As used herein, “aft” refers to the direction associated with the tail(e.g., the back end) of an aircraft, or generally, to the direction ofexhaust of the gas turbine. As used herein, “forward” refers to thedirection associated with the nose (e.g., the front end) of an aircraft,or generally, to the direction of flight or motion.

As used herein, “outboard” may define an element or portion of anelement that is situated radially outer to or away from another,radially inward, element or portion of an element. Thus, an engine coremay be situated radially inboard of an inner fixed structure (“IFS”)and/or a fan casing, as described herein. As used herein, “inboard” maydefine the element or portion of the element that is situated radiallyinward in relation to an outboard element.

Aircraft thrust reversers are often held together with latch assembliesalong various axial distances along the thrust reverser. As describedabove, a typical thrust reverser may include an inner fixed structure(“IFS”). The IFS may comprise two halves, which may be joined togetherwith a latch mechanism (e.g., at the bottom of the IFS). For example,the inner fixed structure of a thrust reverser may include a latchassembly at the bottom of the inner fixed structure to allow the thrustreverser to be hinged open to facilitate access to the engine core.

From time to time, a thrust reverser may experience more pressure thanit is typically designed to handle (i.e., an overpressure event), forexample in the event that an engine bleed air duct bursts. Large ductscome from various stages of compressors in an aircraft engine under hightemperatures and high pressures. In the event one of the ducts bursts,the inner fixed structure tends to be over pressurized. In that regard,an overpressure event tends to exert a radially outward pressure uponthe IFS of a thrust reverser. In response to the radially outwardpressure, a thrust reverser or portions thereof may fail.

Accordingly, pressure relief doors may be provided to release pressurefrom the core cavity in the event of an overpressure event (e.g., aburst pneumatic duct) because typical conventional IFS are more or lesssealed, and thus, do not allow for the release of overpressure.Accordingly, the size of the IFS is commonly sized to withstand anoverpressure event in the event the pressure relief doors were to fail.In that regard, it is desirable for systems and methods that may allowthe thrust reverser IFS to radially expand in response to anoverpressure event in a controlled manner and, thus, reduce the size ofthe IFS. By reducing the size of an IFS, the overall size and weight ofthe nacelle may be reduced, and savings in fuel costs from operation ofan aircraft may be realized. Furthermore, decreasing the weight of theIFS may help cause smaller deflection for fire sealing. Accordingly, invarious embodiments, separation of the latch hook assembly, the latchhousing assembly, and/or the latch assembly may allow the enclosed IFSto open and/or separate. In various embodiments, allowing the enclosedIFS to open and/or separate, may permit a release of overpressure duringa burst duct event, and thus, reduce the size of the IFS.

For example, with temporary reference to FIG. 1, FIG. 1 illustrates aninner fixed structure of an aircraft according to various embodiments.Inner fixed structure 100 may comprise the aft end 120 of the innerfixed structure 100 of a thrust reverser, which may be held together bylatch assembly 110.

Latch assemblies typically comprise a latch mechanism operated by ahandle on the outside of the flow surface. Accordingly, when the handleis operated, the latch mechanism will disengage, allowing access to theinner components of the engine and thrust reverser system. Withreference to FIG. 2A, latch assembly 110 is illustrated from a viewinside inner fixed structure 100 according to various embodiments. Latchassembly 110 may comprise a first latch housing 220, a second latchhousing 221, a first bolt 210, and a second bolt 211 according tovarious embodiments. In various embodiments, first bolt 210 may beinserted into first bushing 230 and second bolt 211 may be inserted intosecond bushing 231 as illustrated in FIG. 2A. In various embodiments,first latch housing 220 may be complementary to the second latch housing221.

According to various embodiments, first latch housing 220 may comprise afirst bushing 230. In various embodiments, first bushing 230 may beintegral to first latch housing 220. For example, with reference to FIG.2B, first latch housing 220 and first bushing 230 are illustrated withfirst bolt 210 transparently shown for improved clarity. First bushing230 may be outboard of the centerline of the inner fixed structure 100according to various embodiments. Similarly, according to variousembodiments, corresponding second latch housing 221 may comprise secondbushing 231, which may be outboard of the centerline of the inner fixedstructure.

According to various embodiments, the bushing may be a deformablebushing at an area at least partially surrounding the bolt, and thedeformable bushing may configured to deform about a radius in responseto a compressive load between about 1,000 lb_(f) (about 4,448 N) toabout 3,000 lb_(f) (about 13,344 N), a compressive load between about1,500 lb_(f) (about 6,672 N) to about 2,500 lb_(f) (about 11,120 N), ora compressive load of about 2,000 lb_(f) (about 8,896 N).

According to various embodiments, the bushing may be configured toirreversibly deform in response to the compressive load. For example,the bushing may comprise various metals or metal alloys capable ofirreversibly deforming in response to a compressive load. Exemplarymetals according to various embodiments include steel, copper, aluminum,titanium, nickel, vanadium, and alloys thereof. The geometry of thebushing is not particularly limited in various embodiments and may bealtered according to various design considerations.

In various embodiments, the bushing may be configured to reversiblydeform in response to the compressive load, for example in response to acompressive load between about 1,000 lb_(f) (about 4,448 N) to about3,000 lb_(f) (about 13,344 N), a compressive load between about 1,500lb_(f) (about 6,672 N) to about 2,500 lb_(f) (about 11,120 N), or acompressive load of about 2,000 lb_(f) (about 8,896 N). For example,various embodiments may comprise bushings made from a polymer, a metal,or combination thereof. Exemplary polymers according to variousembodiments may include rubber, polytetrafluoroethylene (“PTFE”),polyethylene terephthalate (“PET”).

For example, FIG. 2C illustrates first bushing 230 being deformed duringan overpressure event, according to various embodiments. For example,according to various embodiments, during an overpressure event, the twohalves of inner fixed structure 100 may desire to expand due to theinboard pressure exerted on the aft end 120 of inner fixed structure 100(shown in FIG. 1). Accordingly, in various embodiments, the overpressuremay exert a force on the inboard portion of first bushing 230 and firstbolt 210. Likewise, in various embodiments, a force may be exerted onthe inboard portion of corresponding second bushing 231 (shown in FIG.2A). Thus, as demonstrated by FIG. 2C, first bushing 230 may deform 239due to the force exerted on the bushing at the interface with first bolt210, according to various embodiments. In various embodiments, this mayallow the inner fixed structure 100 shown in FIG. 1 to expand and betteraccommodate the overpressure and, thus, prevent damage to the thrustreverser system during an overpressure event.

With reference to FIG. 3A, FIG. 3A illustrates a latch housing assembly,in accordance with various embodiments. Latch housing assembly 300 maycomprise a fuse pin 380 coupled to an inner housing 330 and an outerhousing 320. According to various embodiments, during a burst ductevent, the increase in pressure may cause latch hook 340 to exert atensile load on latch pin 360 contained within slotted hole 350 and,thus, exert tensile load 370 on inner housing 330. The tensile load 370on inner housing may then be exerted on fuse pin 380.

According to various embodiments, fuse pin 380 may be configured toseparate at a predetermined tensile load, for example, 1,000 lb_(f)(about 4,448 N) to about 3,000 lb_(f) (about 13,344 N), a tensile loadbetween about 1,500 lb_(f) (about 6,672 N) to about 2,500 lb_(f) (about11,120 N), or a tensile load of about 2,000 lb_(f) (about 8,896 N). Uponseparation of fuse pin 380, inner housing 330 and outer housing 320 mayseparate, as illustrated in FIG. 3B. Accordingly, in response to atensile load on a latch housing assembly exceeding between about 1,000lb_(f) to about 3,000 lb_(f) in various embodiments, separation of innerhousing 330 and outer housing 320 may occur. The separation of the innerlatch housing and the outer latch housing may allow the two halves ofthe IFS to separate, relieving overpressure during a burst duct event.Thus, in various embodiments, the separation of the latch housingassembly may protect various components of the thrust reverser system.

According to various embodiments, permanent separation may be desirableto indicate an overpressure event (e.g., a duct burst event) tomaintenance ground crew, for example, due to manufacturer or airlinespecifications and/or regulations. As used herein, the term “permanentseparation” may include any separation which is not self-correcting. Forexample, according to various embodiments, fuse pin 380 may separateirreversibly, requiring replacement by maintenance crews.

According to various embodiments, fuse pin 380 is not particularlylimited. For example, in various embodiments, fuse pin 380 may be ashear pin. With reference to FIG. 4A, FIG. 4A illustrates shear pin 480,in accordance with various embodiments. Shear pin 480 may comprise shearpin outer housing 420 and an inner shear pin 400 comprising pin head 410connected to pin body 430 via pin connector 440. According to variousembodiments, in response to tensile forces on shear pin 480, pinconnector 440 may be configured to separate at a predetermined tensileforce (e.g., about 1,000 lb_(f) to about 3,000 lb_(f)). Inner shear pin400 is not particularly limited and may comprise various geometries ormay be comprised of various materials. Exemplary materials includealuminum, copper, nickel, silver, tin, steel and alloys thereof.

With reference to FIG. 4B, FIG. 4B illustrates shear pin 480 separatingin accordance with various embodiments. In various embodiments, whentensile force 470 is exerted on pin body 430 (e.g., in the negativey-direction), the tensile load may be transferred to pin connector 440(shown in FIG. 4A). The tensile force on pin connector 440 may then betransferred to pin head 410, which in various embodiments, may becomeconstrained against shear pin outer housing 420. In various embodiment,this may cause pin connector 440 to separate into a first part 441(connected to pin head 410) and a second part 442 (connected to pin body430).

According to various embodiments, a shear pin may be desirable, becausepermanent separation of a shear pin may indicate an overpressure eventto maintenance ground crews. Moreover, in various embodiments, use of ashear pin may be desired because of reduced costs and ease ofreplacement by maintenance crews. In various embodiments, this may allowfor improved aircraft turnaround time.

According to various embodiments, reversible separation may bedesirable, for example, to reduce maintenance costs and improve aircraftturnaround time. As used herein, the term “reversible separation” mayinclude any separation which tends to be self-correcting. For example,according to various embodiments and with reference to FIG. 3C, a spring390 may reversibly extend during an overpressure event (e.g., a ductburst event) and may return to the spring's original position once thepressure decreases to acceptable operating pressures.

Thus, in various embodiments, fuse pin 380 may be replaced with spring390 to allow for reversible separation of latch housing assembly 300.With reference to FIG. 3C, FIG. 3C illustrates a latch housing assemblyin accordance with various embodiments. Latch housing 301 may comprisespring 390 coupled to an inner housing 330 and an outer housing 320having an inner surface coupled to an outer surface of the inner housing330 via spring 390. According to various embodiments, during a burstduct event, the increase in pressure may cause latch hook 340 to exert atensile load on latch pin 360 contained within slotted hole 350 and,thus, exert tensile load 370 on inner housing 330. The tensile load 370on inner housing may then be exerted on spring 390.

In various embodiments, spring 390 (shown in FIG. 3C) may have a springconstant between about 1,000 lb_(f)/ft (about 1,356 N/m) to about 3,000lb_(f)/ft (about 4,067 N/m), between about 1,500 lb_(f)/ft (about 2,034N/m) to about 2,500 lb_(f)/ft (about 3,390 N/m), or about 2,000lb_(f)/ft (about 2,711 N/m) and, thus, may permit temporary separationof inner housing 330 and outer housing 320 during an overpressure event(e.g., a duct burst event). Accordingly, in response to a tensile loadon a latch housing assembly (e.g., due to an overpressure event),separation of the latch housing assembly may relieve internal pressureon the IFS and, thus, protect various aircraft components.

In various embodiments, the separation of a latch hook assembly may bedesired. With reference to FIG. 5A, FIG. 5A illustrates a latch hookassembly in accordance with various embodiments. In various embodiments,latch hook assembly 500 may comprise a latch hook 560 coupled to a latchhousing 530, a weak point 540 in the latch housing disposed between aninboard mount 520 and an outboard mount 521, and catch pins 510 mountedto inboard mount 520 and outboard mount 521. In various embodiments andas previously described above, complimentary latch hook assemblies maybe used together so that latch hook 560 engages a latch pin disposed ina slotted hole of a corresponding latch hook assembly. For example,latch pin 575 in slotted hole 570 may receive a latch hook from acorresponding latch hook assembly.

According to various embodiments, weak point 540 may be a portion oflatch hook assembly 500 which is configured to separate at apredetermined tensile load, for example, 1,000 lb_(f) (about 4,448 N) toabout 3,000 lb_(f) (about 13,344 N), a tensile load between about 1,500lb_(f) (about 6,672 N) to about 2,500 lb_(f) (about 11,120 N), or atensile load of about 2,000 lb_(f) (about 8,896 N). The weak point isnot particularly limited and may comprise the same or different materialas latch housing 530. For example, in various embodiments, weak point540 may comprise a material with a lower tensile strength than latchhousing 530. In various embodiments, weak point 540 may comprise thesame materials as latch housing 530, but may have a lower tensilestrength due to the configuration of weak point 540, for example, due todrilled grooves or other configuration designed to lower the tensilestrength of weak point 540.

In various embodiments, latch hook assembly may comprise catch pins 510.In various embodiments, catch pins 510 may be configured to withstandthe tensile forces during an overpressure event. According to variousembodiments, catch pins 510 may be longer than weak point 540 and, thusallow the IFS to expand during an overpressure event, while limiting theentire distance the latch hook assembly is allowed to separate.

With reference to FIG. 5D, FIG. 5D illustrates a latch hook assemblyduring or after an overpressure event according to various embodiments.As previously described, in various embodiments, latch hook assembly 500may be configured to irreversibly separate at weak point 540. Accordingto various embodiments, tensile forces on latch hook 560 may then betransferred to latch housing 530 (shown in FIG. 5A), which may thenseparate into inboard latch housing fragment 531 and outboard latchhousing fragment 532, as illustrated in FIG. 5D. According to variousembodiments, catch pins 510 coupled with inboard mount 520 and outboardmount 521 may then prevent separation of inboard latch housing fragment531 and outboard latch housing fragment 532 beyond a predetermineddistance. Thus, in various embodiments, catch pins 510 may be able towithstand the tensile forces during an overpressure event (e.g., a ductburst event). Accordingly, in various embodiments, latch hook assembly500 may be configured to release overpressure in the IFS of a thrustreverser system while ensuring the IFS remains coupled to the latch hookassembly.

According to various embodiments, a latch hook assembly configured toreversibly separate may be desired. With reference to FIG. 5B, FIG. 5Billustrates latch hook assembly 501 where the catch member is a catchspring. Latch hook assembly 501 may comprise a latch hook 560 coupled toa latch housing 530, a weak point 540 in the latch housing disposedbetween an inboard mount 520 and an outboard mount 521, and a catchsprings 590 mounted to inboard mount 520 and outboard mount 521. Invarious embodiments and as previously described above, complimentarylatch hook assemblies may be used together so that latch hook 560engages a latch pin disposed in a slotted hole of a corresponding latchhook assembly. For example, latch pin 575 in slotted hole 570 mayreceive a latch hook from a corresponding latch hook assembly.

According to various embodiments, weak point 540 may be a portion oflatch hook assembly 500 which is configured to separate at apredetermined tensile load. The weak point is not particularly limitedand may comprise the same or different material as latch housing 530.For example, in various embodiments, weak point 540 may comprise amaterial with a lower tensile strength than latch housing 530. Invarious embodiments, weak point 540 may comprise the same materials aslatch housing 530, but may have a lower tensile strength due to theconfiguration of weak point 540, for example, due to drilled grooves orother configuration designed to lower the tensile strength of weak point540. In various embodiments, weak point 540 may comprise an interfacebetween two parts of latch housing 530 between outboard mount 521 andinboard mount 520. Thus, in various embodiments, weak point 540 may beconfigured to separate in response to a tensile load to yield an inboardlatch housing fragment 531 and an outboard latch housing fragment 532,as demonstrated in FIG. 5E.

FIG. 5E illustrates a latch hook assembly during an overpressure eventin accordance with various embodiments. As described above, latch hookassembly 501 may be held together by weak point 540, which may separateduring an overpressure event. During an overpressure event, a tensileforce may be exerted on latch hook assembly 501 causing weak point 540to separate. In various embodiments, catch springs 590 may be configuredto expand during an overpressure event and, thus, may allow forreversible separation of latch hook assembly 501. According to variousembodiments, catch springs 590 may have a spring constant between about1,000 lb_(f)/ft (about 1,356 N/m) to about 3,000 lb_(f)/ft (about 4,067N/m), between about 1,500 lb_(f)/ft (about 2,034 N/m) to about 2,500lb_(f)/ft (about 3,390 N/m), or about 2,000 lb_(f)/ft (about 2,711 N/m)and, thus, may permit temporary separation of the IFS according tovarious embodiments.

Moreover, in various embodiments, latch hook assemblies may comprise twoor more catch members (e.g., catch pins 510 and catch springs 590). Forexample, with reference to FIG. 5C, FIG. 5C illustrates a latch hookassembly 502 comprising a first catch member (catch pins 510) and asecond catch member (catch springs 590), according to variousembodiments. Latch hook assembly 502 may comprise a latch hook 560coupled to a latch housing 530, a weak point 540 in the latch housingdisposed between an inboard mount 520 and an outboard mount 521, and aboth catch pins 510 and catch springs 590 mounted to inboard mount 520and outboard mount 521. In various embodiments and as previouslydescribed above, complimentary latch hook assemblies may be usedtogether so that latch hook 560 engages a latch pin disposed in aslotted hole of a corresponding latch hook assembly. For example, latchpin 575 in slotted hole 570 may receive a latch hook from acorresponding latch hook assembly.

According to various embodiments, weak point 540 may be a portion oflatch hook assembly 500 which is configured to separate at apredetermined tensile load. The weak point is not particularly limitedand may comprise the same or different material as latch housing 530.For example, in various embodiments, weak point 540 may comprise amaterial with a lower tensile strength than latch housing 530. Invarious embodiments, weak point 540 may comprise the same materials aslatch housing 530, but may have a lower tensile strength due to theconfiguration of weak point 540, for example, due to drilled grooves orother configuration designed to lower the tensile strength of weak point540. In various embodiments, weak point 540 may comprise an interfacebetween two parts of latch housing 530 between outboard mount 521 andinboard mount 520.

According to various embodiments, incorporation of both catch pins 510and catch springs 590 may allow for a latch hook assembly configured toreversibly separate, and, in various embodiments, may help prevent catchsprings 590 from being stretched beyond their elastic limit.Accordingly, in various embodiments, catch pins 510 may be configured toprevent the separation of latch hook assembly beyond the elastic limitof catch springs 590.

In various embodiments, separation of the latch hook assembly, the latchhousing assembly, and/or the latch assembly may permit a release ofpressure in during a burst duct event. Accordingly, in variousembodiments, separation of the latch hook assembly, the latch housingassembly, and/or the latch assembly may permit smaller inner fixedstructures to be used in aircraft, thus saving on weight and fuel coststhroughout the life of the aircraft. Furthermore, failure of the latchhook assembly, the latch housing assembly, and/or the latch assemblyaccording to various embodiments may provide improved protection toengine and thrust reverser components during an overpressure event(e.g., a duct burst event) and may be easily replaceable by maintenancepersonnel. In various embodiments, the various latch hook assemblies arenot particularly limited and can be modified according to manufacturer,customer (e.g., an airline), and/or governmental regulations.

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent exemplary functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the disclosed embodiments. The scope of the claimedembodiments is accordingly to be limited by nothing other than theappended claims, in which reference to an element in the singular is notintended to mean “one and only one” unless explicitly so stated, butrather “one or more.” Moreover, where a phrase similar to “at least oneof A, B, or C” is used in the claims, it is intended that the phrase beinterpreted to mean that A alone may be present in an embodiment, Balone may be present in an embodiment, C alone may be present in anembodiment, or that any combination of the elements A, B and C may bepresent in a single embodiment; for example, A and B, A and C, B and C,or A and B and C. Different cross-hatching is used throughout thefigures to denote different parts but not necessarily to denote the sameor different materials.

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “one embodiment”, “an embodiment”, “anexample embodiment”, etc., indicate that the embodiment described mayinclude a particular feature, structure, or characteristic, but everyembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed. After reading the description, it will be apparent to oneskilled in the relevant art(s) how to implement the disclosure inalternative embodiments.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element herein is to be construed under theprovisions of 35 U.S.C. § 112(f), unless the element is expresslyrecited using the phrase “means for.” As used herein, the terms“comprises”, “comprising”, or any other variation thereof, are intendedto cover a non-exclusive inclusion, such that a process, method,article, or apparatus that comprises a list of elements does not includeonly those elements but may include other elements not expressly listedor inherent to such process, method, article, or apparatus.

What is claimed is:
 1. A latch hook assembly, comprising: a latchhousing including a first slotted hole; a first inboard mount coupled tothe latch housing; a first outboard mount coupled to the latch housing;a latch hook coupled to the latch housing; a second inboard mountcoupled to the latch housing; a second outboard mount coupled to thelatch housing; a weak point in the latch housing disposed between thefirst inboard mount and the first outboard mount; a first latch pindisposed in the first slotted hole of the latch housing; and a firstcatch member mounted to the first inboard mount and the first outboardmount, a second catch member mounted to the second inboard mount and thesecond outboard mount, wherein the first catch member and the secondcatch member are configured to allow an inner fixed structure (IFS) toexpand during an overpressure event; wherein the latch hook isconfigured to engage a second latch pin.
 2. The latch hook assembly ofclaim 1, wherein the weak point is configured to fail in response to atensile load between about 1,000 lb_(f) to about 3,000 lb_(f) to yieldan inboard latch housing fragment and an outboard latch housingfragment.
 3. The latch hook assembly of claim 1, wherein the weak pointcomprises the same material as the latch housing.
 4. The latch hookassembly of claim 1, wherein the weak point comprises a material with alower tensile strength than the latch housing.
 5. The latch hookassembly of claim 1, wherein the weak point is configured to have alower tensile strength than the latch housing.
 6. The latch hookassembly of claim 1, wherein the first catch member is a first catch pinand the second catch member is a second catch pin.
 7. The latch hookassembly of claim 6, further comprising a third catch member and afourth catch member, the third catch member including a first catchspring, the third catch member mounted to the first inboard mount andthe first outboard mount, the second catch member including a secondcatch spring, the second catch member mounted to the second inboardmount and the second outboard mount.
 8. The latch hook assembly of claim1, wherein the first catch member is a first catch spring, and whereinthe second catch member is a second catch spring.